Cylinder head



Feb. 25, 1941.

l. E. sKE 2,232,759

CYL NDER HEAD Filed Oct. 14, 1939 N V 3 Irving 5.654

6 y In vmgor wnzi-y Y Patented Feb. 25, 1941 UNITED STATES PATENT OFFICE 5 Claims.

My present invention relates to improvements in cylinder heads for internal combustion engines, and particularly to the combustion chamber of such engines, and- The objects of inventive improvements are, first, to improve combustion of the fuel charge compressed within the combustion chamber; sec- 0nd, to improve the distribution'of the fuel flame; third, to increase the power of the engine; and, fourth, to improve the operation of the engine and. produce smooth, quiet running of the engine.

These named objects and other objects that appear from a perusal of the following description are accomplished by the structure disclosed in the accompanying drawing, in which:

Figure 1 is a plan view of a cylinder head taken from its plane side and having depressed therein my improved combustion chamber.

Figure 2 is a transverse sectional view of my cylinder head taken on line CC of Figure 1 having therein my improved combustion chamber intersected by said line C-C.

Figure 3 is a fragmentary sectional view taken longitudinally of my cylinder head, taken on line A-A through the combustion chamber as of Figure 1.

Throughout the several views of the drawing, similar reference numerals designate similar parts or portions of my cylinder head, and referring thereto:

Numeral I designates the body of my improved internal combustion engine cylinder head, having a plane faced wall 2 for closing the cylinder of the engine and a cooling fluid chamber 3 into which extends wall 4 bounding the combustion chamber 5, the said wall 4 extending around the combustion chamber in a series of reverse curves, 6, I, 8, 9, II], II, I2, I3, I4, I5, and over the top of the chamber to forma roof 4 for the said combustion chamber. The said roof designated by numeral 4' is in incline relation to the plane face I6 of the plane face wall 2, and is joined to said plane faced wall by combustion chamber bounding wall 4 having a greater height adjacent the curve I2 than at the location I8 adjacent the curve 6 over the top of the cylinder bore I9 of the cylinder block 20; and longitudinally of the body I, a greater height from the plane face I6 at curve I3 adjacent the spark plug hole I'I than at the curve 9 of the wall 4. I6- designates a gasket between the body I and cylinder block 20.

Numeral 2| designates the spark plug screw threaded into the spark plug hole and for producing an electric spark whereby the charge of compressed fuel within the combustion chamber and clearance spaces between the cylinder head and the piston of the engine is ignited.

In Figure 1, the position of the cylinder bore I9, when the cylinder head is in place on the cylinder block, is designated by the broken circular line I9.

In my improved combustion chamber as herein described, by varying the inclinations of the combustion chamber roof wall 4 in the direction of the lines C-C and A-A, of Figure 1, it will be obvious to those skilled in the art that the distribution of the combustible portions of the fuel charge compressed within the combustion chamber can be easily varied in its relation to the total" charge and spark ignition location, so as to conform to the features of applicants United States Letters Patent No. 2,138,131 for producing engine smoothness of operation. I

The greatest depth of my combustion chamber preferably lies in the zone containing the ignition spark hole I1 bounded by the curve I2 and I3, and an intermediate depth in the zone near the opposite wall adjacent the curve 9. The greater depth of the spark ignition zone will enclose a larger portion of the fuel charge, and because of its large volume it will contribute greatly to the rapid burning of the fuel, which is essential to the improved production of power,

low fuel consumption and smoothness of engine]? operation.

A further important feature in having the greatest depth of the combustion chamber in the zone of ignition is the facility it affords in promoting easy starting of the engine in low atmospheric temperatures, where it is frequently necessary to draw into the combustion chamber a large quantity of wet or highly saturated fuel in order to secure a sufficient amount of vaporized fuel that will ignite by the ignition spark to start is much greater than the volume of fuel located in the zone 5. The effect of gradually reducing the depth from curve I3 to curve 9 along the'line A-A is to limit the velocity of the pressure rise of combustion and surface temperatures at zone 5, as the combustion flame front advances from the ignition point located at the spark plug hole and which results in a greatly improved control over detonation and a lower average temperature for the engine valves.

To bring about the most ideal distribution of fuel volume for a smooth-running engine, the depth of the chamber at curve 9 should be between 45 and 60 percent of the depth of chamber adjacent curve I3. When the ratio of depths is less than 45 per cent there will be too much fuel volume Within the spark ignition zone, and too little over the other valve, resulting in loss of power, while with too great a ratio exceeding 60 percent, there will be too little volume surrounding, the ignition spark and too much over the exhaust valve,=which results in loss of power and poor starting in cold Weather.

When the ignition point is located over the fuel intake valve zone, as recommended for my combustion chamber, the large volume. of fuel burned at that location tends to raise the temperature of the intake valve and. thereby acts to aid vaporization of the incoming fuel. Because of the least depth portion of the chamber occurring over the exhaust valve in zone 5, it will contain the least volume of the fuel charge, and therefore a minimum of heat will be transmitted to said valve.

To further reduce the pressure shock on the piston of the engine, such as caused by a too rapid rise of the pressure, the roof wall 4 is inclined along the line CC, so as to produce a greater depth of chamber adjacent the curves H], II and I2, than at the curve 6 over the piston. To minimize roughness it has been found important to regulate the slope of the roof wall 4 in the line CC, from the curve H to the curve 6 over the piston l9, so that the angle it makes with the plane face l6 will lie between 3 and 8 degrees. If made less than 3 degrees, too much fuel will be burned over the zone of the piston, causing engine roughness and detonation, while if the slope is made to exceed 8 degrees, too much fuel will be burned in the zone of the valves, which will also induce detonation and overheating of the exhau'st valve.

A further advantage derived from sloping the roof wall 4' in the two directions of lines AA and C--C is the violent turbulence of the fuel set up by the motion of the piston during the compression of the fuel charges. Since the depth of the combustion chamber at one edge of the piston along curve I5 is approximately twice as deep as the edge along curve I, the voliune of fuel fiow on the deep side will be double that of the shallow side, thus producing a high turbulent effect within the chamber that assists in the thorough mixing of the fuel with air previous to ignition. Such a condition serves to increase the power and economy of the engine, since a leaner mixture of fuel with air can be ignited and burned.

It is obvious that by sloping the roof wall 4' in the two directions AA and CCl it becomes easily possible to produce the most ideal distribution of fuel volume to improve power output, control of detonation and smoothness of engine operation.

In my cylinder head, a combustion chamber having a plane or slightly arched roof generally inclined to the plane face of the head and because of its gradual slope downward from the zone of ignition, without obstructions to the travel of the flame of combustion, accumulates a minimum of carbon deposit. Also with the plane smooth surface without obstructions, the roof of the combustion chamber absorbs the minimum of heat from the combustion flame passing over it, since the plane surface of the combustion chamber roof offers a minimum of resistance to the passage of the combustion flame. The plane surface roof absorbs less heat than in a combustion chamber having a wavy surface roof and therefore avoids the formation of hot spots in the roof. 7

Having described my invention, the rights which I desire to secure are set forth in the following claims:

1. In a cylinder head for internal combustion engines and comprising a cylinder head body having a plane face for closing the engine cylinder bore, a combustion chamber extending into the body from the plane face and over a portion of the cylinder bore and having therein an ignition spark plug in spacedapart relation to its portion over the cylinder bore, the said combustion chamber having a plane faced roof wall in less than 8 degrees incline relation to the said plane face of the said body transversely and longitudinally of the combustion chamber with its greatest distance from said plane face adjacent the said spark plug and its least distance from the plane face at its portion over the said cylinder bore.

2. In a cylinder head for internal combustion engines and comprising a cylinder head body having a plane face for closing the engine cylinder bore, a combustion chamberextending into the .body from the plane face and over a portion of the cylinder bore and having therein an ignition spark plug in spaced apart relation to its portion over the cylinder bore, the said combustion chamber having a roof with a plane ceiling, the said roof and ceiling inclined from adjacent the spark plug hole progressively toward the said plane face transversely and longitudinally of the cylinder head body.

3. In a cylinder head for internal combustion engines and comprising a cylinder head body having a plane face for closing the engine cylinder bore, a combustion chamber extending into the body from the plane face and over a portion of the cylinder bore and having therein an ignition spark plug in spaced apart relation to its portion over the cylinder bore, the said combustion chamber having its greatest depth adjacent the spark plug hole and gradually diminishing in depth in all radial directions from adjacent the said spark plug hole.

4. In a cylinder head for internal combustion engines and comprising a cylinder head body having a plane face for closing the engine cylinder bore, a combustion chamber extending into the body from the plane face and over a portion of the cylinder bore and having therein an ignition spark plug in spaced apart relation to its portion over the cylinder bore, and an exhaust valve extending therein in spaced relation to the said spark plug hole, the said combustion chamber having a greater depth adjacent the sad spark plug hole and a lesser depth over the cylinder bore and over the said exhaust valve.

5; In a cylinder head for internal combustion engines and comprising a cylinder head body having a plane face for closing the engine cylinder bore, a combustion chamber extending into the body from the plane face and over a portion of the cylinder bore and having therein an ignition spark plug in spaced apart relation to its portion over the cylinder bore, and a plurality of valves projecting therein in spaced apart relation to each other with one of said valves below the said spark plug hole, the said combustion chamber having a roof in incline relation to the said plane face with its greatest distance from said face adjacent the said spark plug hole with a lesser distance from said plane face over the cylinder bore, and at the valve in spaced apart relation tothe said valve adjacent the said spark plug hole.

' IRVING E. ASKE. 

